Apt to be looked up to? (4)

I believe the answer is:

tall

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'be looked up to?' is the definition.
(I've seen this in another clue)

I don't understand how the rest of the clue works.

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(Other definitions for tall that I've seen before include "Unbelievable" , "Lofty; unlikely" , "description of a giraffe?" , "Above average height" , "Remarkable" .)

I've seen this clue in the Evening Standard.

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